CERN has revealed plans for a gigantic successor of the giant atom smasher LHC, the biggest machine ever built. Particle physicists will never stop to ask for ever larger big bang machines. But where are the limits for the ordinary society concerning costs and existential risks?

CERN boffins are already conducting a mega experiment at the LHC, a 27km circular particle collider, at the cost of several billion Euros to study conditions of matter as it existed fractions of a second after the big bang and to find the smallest particle possible – but the question is how could they ever know? Now, they pretend to be a little bit upset because they could not find any particles beyond the standard model, which means something they would not expect. To achieve that, particle physicists would like to build an even larger “Future Circular Collider” (FCC) near Geneva, where CERN enjoys extraterritorial status, with a ring of 100km – for about 24 billion Euros.

Experts point out that this research could be as limitless as the universe itself. The UK’s former Chief Scientific Advisor, Prof Sir David King told BBC: “We have to draw a line somewhere otherwise we end up with a collider that is so large that it goes around the equator. And if it doesn’t end there perhaps there will be a request for one that goes to the Moon and back.”

“There is always going to be more deep physics to be conducted with larger and larger colliders. My question is to what extent will the knowledge that we already have be extended to benefit humanity?”

International critics of the high energy experiments planned to start soon at the particle accelerator LHC at CERN in Geneva have submitted a request to the Ministers of Science of the CERN member states and to the delegates to the CERN Council, the supreme controlling body of CERN.

The paper states that several risk scenarios (that have to be described as global or existential risks) cannot currently be excluded. Under present conditions, the critics have to speak out against an operation of the LHC.

The submission includes assessments from expertises in the fields markedly missing from the physicist-only LSAG safety report — those of risk assessment, law, ethics and statistics. Further weight is added because these experts are all university-level experts – from Griffith University, the University of North Dakota and Oxford University respectively. In particular, it is criticised that CERN’s official safety report lacks independence – all its authors have a prior interest in the LHC running and that the report uses physicist-only authors, when modern risk-assessment guidelines recommend risk experts and ethicists as well.